1. Field of the Invention
The present invention relates to a system and method for integrated tire pressure monitoring and vehicle passive entry.
2. Background
It is known in the automotive industry to provide for wireless monitoring of vehicle tire parameters, particularly tire pressure. In such tire pressure monitoring systems, monitors which typically include pressure sensors and radio frequency (RF) transmitters are mounted inside each tire, usually adjacent the inflation valve stem. In each tire, the tire pressure sensed by the tire pressure sensor is transmitted by the transmitter to a receiver/controller located on-board the vehicle. The tire pressure information delivered to the receiver/controller by the RF signals from the transmitters is subsequently conveyed to a vehicle operator or occupant, typically in the form of a display. Exemplary tire pressure monitoring systems are described and shown in U.S. Pat. Nos. 6,112,587 and 6,034,597.
It is also known in the automotive industry to provide for remote vehicle access, such as through the use of remote keyless entry (RKE) systems. Such RKE systems typically use a hand-held remote transmitter, which is commonly referred to as a xe2x80x9cfobxe2x80x9d or xe2x80x9ccard.xe2x80x9d Currently available RKE fobs may be separate units, or may be part of an ignition key head. Such RKE fobs generally transmit radio frequency (RF) signals to a vehicle in order to lock or unlock vehicle doors, open or close a vehicle sliding door, unlock a vehicle trunk, activate internal and/or external vehicle lights, activate a xe2x80x9cpanicxe2x80x9d alarm, and/or perform a variety of other functions.
RKE systems may be characterized as active or passive systems. In active RKE systems, a switch or pushbutton on the remote transmitter must be activated by an operator in order to have a desired remote access function performed, such as locking or unlocking the vehicle doors. In passive RKE systems, however, no such switch or pushbutton activation by an operator is required in order to perform a desired remote access function.
More specifically, in a passive RKE system, a remote transponder, which again may be referred to as a xe2x80x9cfobxe2x80x9d or a xe2x80x9ccard,xe2x80x9d is typically provided for communicating with a transponder and/or control unit installed in the vehicle. The vehicle transponder and/or control unit is provided in communication with door locking mechanisms to lock and unlock the vehicle doors in response to lock or unlock signals received from the remote transponder within some pre-defined range. In that regard, the remote transponder is carried by an operator and is designed to automatically unlock the vehicle as the operator approaches the vehicle, without the need for operation of any switch or pushbutton by the operator. Similarly, the system is further designed to automatically lock the vehicle as the operator, carrying the remote transponder, moves away from the vehicle.
Exemplary passive entry systems for vehicles are described in U.S. Pat. No. 4,873,530 issued to Takeuchi et al. and entitled xe2x80x9cAntenna Device In Automotive Keyless Entry System;xe2x80x9d U.S. Pat. No. 4,942,393 issued to Waraksa et al. and entitled xe2x80x9cPassive Keyless Entry System;xe2x80x9d U.S. Pat. No. 5,499,022 issued to Boschini and entitled xe2x80x9cRemote Control System For Locking And Unlocking Doors And Other Openings In A Passenger Space, In Particular In A Motor Vehicle;xe2x80x9d U.S. Pat. No. 5,751,073 issued to Ross and entitled xe2x80x9cVehicle Passive Keyless Entry And Passive Engine Starting System;xe2x80x9d U.S. Pat. No. 6,049,268 issued to Flick and entitled xe2x80x9cVehicle Remote Control System With Less Intrusive Audible Signals And Associated Methods;xe2x80x9d and U.S. Pat. No. 6,236,333 issued to King and entitled xe2x80x9cPassive Remote Keyless Entry System.xe2x80x9d
Such prior art tire pressure monitoring and passive entry systems, however, are independent, distinct systems. That is, such systems do not interact with one another or share components. In that regard, the use of passive entry information for regulating tire pressure monitoring would improve operational efficiency. Such a system and method would also preferably integrate tire pressure monitoring and vehicle passive entry, such as through the use of shared, combined or integrated components, thereby reducing cost.
Accordingly, the present invention provides a system and method for integrated tire pressure monitoring and vehicle passive entry.
According to the present invention, then, a system is provided for remote monitoring of tire pressure in a vehicle having a plurality of tires. The system comprises a plurality of tire monitors, each monitor for mounting in one of the plurality of tires to monitor tire pressure. Each monitor comprises a transponder for transmitting a signal representative of the tire pressure and for receiving a control signal for use in regulating transmission of the tire pressure signal. The system further comprises a receiver for mounting on-board the vehicle for receiving the tire pressure signals transmitted by the transponders and for receiving a passive entry signal transmitted by a remote passive entry device, and a transmitter for mounting on-board the vehicle for transmitting to the transponders the control signal for use in regulating transmission of the tire pressure signals. The system still further comprises a controller for mounting on-board the vehicle and to be provided in communication with the receiver and the transmitter. The controller is for conveying tire pressure information to a vehicle occupant based on the tire pressure signals, determining whether the vehicle is occupied based on the passive entry signal, and generating the control signal for use in regulating transmission of the tire pressure signals. The control signal is operative to halt transmission of the tire pressure signals by the transponders when the vehicle is unoccupied.
Also according to the present invention, another system is provided for remote monitoring of tire pressure in a vehicle having a plurality of tires. The system comprises a plurality of tire monitors, each monitor for mounting in one of the plurality of tires to monitor tire pressure. Each monitor comprises a transponder for transmitting a signal representative of the tire pressure and for receiving a control signal operative to regulate transmission of the tire pressure signal. The system further comprises at least one receiver for mounting on-board the vehicle for receiving the tire pressure signals transmitted by the transponders and for receiving a passive entry signal transmitted by a remote passive entry device. The system still further comprises a controller for mounting on-board the vehicle and to be provided in communication with the at least one receiver, the controller for conveying tire pressure information to a vehicle occupant based on the tire pressure signals, determining whether the vehicle is occupied based on the passive entry signal, and generating the control signal for use in regulating transmission of the tire pressure signals. The control signal is operative to halt transmission of the tire pressure signals by the transponders when the vehicle is unoccupied.
Still further according to the present invention, a method is provided for monitoring tire pressure in a vehicle having a plurality of tires. The method comprises transmitting from a tire a signal representative of a tire pressure, and receiving at the tire a control signal for use in regulating transmission of the tire pressure signal. The method further comprises receiving at the vehicle the tire pressure signal and a passive entry signal, and conveying tire pressure information to a vehicle occupant based on the tire pressure signal. The method still further comprises determining whether the vehicle is occupied based on the passive entry signal, and transmitting from the vehicle the control signal for use in regulating transmission of the tire pressure signal, wherein the control signal is operative to halt transmission of the tire pressure signal when the vehicle is unoccupied.
These and other features and advantages of the present invention will be readily apparent upon consideration of the following detailed description of the invention in conjunction with the accompanying drawings.